JP2012155170A - Conveying device, image forming device and conveying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conveying device capable of executing predetermined processing at an accurate position with respect to both front and rear surfaces of a target, and further to provide an image forming device and a conveying method.SOLUTION: A conveying device comprises: reading sensors 37a and 37b for detecting positions of through holes 67a disposed apart from each other in a conveyance direction along a lengthwise direction of a sheet with respect to the sheet having a long shape; and a first driving roller 22a for applying tensile force with respect to the sheet in the conveyance direction such that a separating distance between through holes 67a in the conveyance direction of the sheet becomes a preset distance based on detection results of the reading sensors 37a and 37b.

Description

  The present invention relates to a transport device that transports a long target, an image forming apparatus including the transport device, and a transport method.

  Conventionally, as an example of an image forming apparatus that forms an image on a target, a reference position mark is printed on the target, and the print position of the image is aligned with the target based on the position information of the reference position mark. Such a printer has been proposed (for example, Patent Document 1).

  The printer described in Patent Document 1 includes a first printing device that prints a toner mark (reference position mark) together with an image on the surface of a web (target), and a second printer that prints an image on the back surface of the web. Printing apparatus. In these printing apparatuses, at the time of printing processing, after an electrostatic latent image is formed on the photosensitive drum by the light output from the light source, the developer is supplied to the electrostatic latent image, thereby the photosensitive drum. A toner image is formed on top. Then, after transferring the toner image formed on the photosensitive drum to the web, the web is nipped by a heated roller pair so that the toner image is fixed to the web.

  In the printer described in Patent Document 1, the web surface of the first printing apparatus is controlled by controlling the web conveyance speed according to the detection timing at which the mark sensor of the second printing apparatus detects the toner mark. The printing position of the image formed on the second printing apparatus is aligned with the printing position of the image formed on the back surface of the web in the second printing apparatus.

JP 2005-205759 A

  By the way, in the printer described in Patent Document 1, heat is applied to the web when the toner image formed on the surface of the web is fixed to the web, so that the web may be thermally contracted. In this case, in the printer described above, the detection timing of the toner mark is changed due to the contraction of the web, and the printing position of the image formed on the surface of the web in the first printing device and the second printing device In this case, the printing position of the image formed on the back surface of the web cannot be aligned. Therefore, the second printing is performed so that the printing position of the image formed on the front surface of the web in the first printing apparatus is aligned with the printing position of the image formed on the back surface of the web in the second printing apparatus. Until the web conveyance speed in the apparatus is changed, there is a possibility that the print positions of images printed on both the front and back surfaces of the web cannot be aligned.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a transport apparatus, an image forming apparatus, and a transport method capable of performing predetermined processing at accurate positions on both the front and back surfaces of a target. It is to provide.

  In order to achieve the above object, the transport apparatus of the present invention includes a first reference position mark and a first reference mark that are provided at an interval in the transport direction along the length direction of the long target. A position sensor that detects the position of the second reference position mark, and a separation distance between the first reference position mark and the second reference position mark in the transport direction of the target based on a detection result of the position sensor. Tension applying means for applying tension to the target in the transport direction so as to have a preset set distance was provided.

  According to the above configuration, even when the target is contracted in the transport direction, the tension applying unit is configured so that the distance between the reference position marks is set in advance based on the detection result of the position sensor. By applying a tension to the target, it is possible to suppress the contracted state of the target in the transport direction. Therefore, a predetermined process can be performed at an accurate position on both the front and back surfaces of the target.

  In the transport device of the present invention, the tension applying unit applies tension to the target within a range in which an extension amount in the transport direction based on the tension applied to the target does not exceed a preset threshold.

  According to the above configuration, the extension amount in the target transport direction is limited to a range that does not exceed the threshold value. Therefore, since excessive tension acts on the target can be avoided, the target can be prevented from breaking.

  In addition, the transport apparatus according to the present invention further includes detection means for detecting whether or not the target is broken, and notification means for performing error notification when the detection means detects breakage of the target.

According to the said structure, the user can grasp | ascertain quickly and reliably that the target broke by error notification.
In order to achieve the above object, an image forming apparatus according to the present invention includes a transport device having the above-described configuration, an image forming control unit that performs image forming processing on a target transported by the transport device, and the image forming device. Fixing means for thermally fixing an image formed on the target by the control means.

According to the said structure, the effect similar to invention of the said conveying apparatus is acquired.
In the image forming apparatus according to the aspect of the invention, the tension applying unit may perform a heat fixing process on the target with the fixing unit with respect to the target on which the image forming process has been performed with the image forming control unit. Before the fixing, a tension is further applied in the transport direction of the target by a distance corresponding to an estimated value of the thermal contraction amount of the target accompanying the thermal fixing process by the fixing unit.

  According to the above configuration, since tension is applied to the target so as to offset the thermal contraction amount of the target when the image is thermally fixed to the target, the image from the target subjected to the heat fixing process is applied. The die cutting process can be performed more accurately.

  In the image forming apparatus according to the aspect of the invention, the image formation control unit is configured to sequentially execute image formation processing on the front surface and the back surface of the target, and the tension applying unit includes the surface of the target and the back surface of the target. Among the image forming processes for the back surface, at least before the image forming process for the back surface is performed, a tension is further applied to the target.

  According to the above configuration, even when the target is thermally contracted when the image formed on the surface of the target is heat-fixed, the target is stretched by applying tension to the back surface of the heat-shrinkable target. An image forming process is performed in the state. Therefore, even when an image is thermally fixed to a target having heat shrinkability, an image forming process can be accurately performed on both the front and back surfaces of the target.

  In the image forming apparatus according to the aspect of the invention, the image forming control unit may reciprocate a liquid ejecting head that forms an image by ejecting liquid onto the target while reciprocating in a direction intersecting the target transport direction. The liquid ejection timing can be adjusted in accordance with the amount of deviation between the image forming position during movement and the image formation position during backward movement, and the liquid ejection is performed based on the amount of extension of the target by applying tension. Change the timing adjustment amount.

  Generally, when an image is thermally fixed to a target, the thickness of the target changes due to the application of tension. Then, the amount of deviation of the landing position of the liquid during the forward movement and the backward movement of the liquid ejecting head changes. In this regard, according to the above configuration, the amount of adjustment of the ejection timing of the liquid from the liquid ejecting head is changed according to the amount of extension of the target by applying the tension, so that the liquid ejecting head can be moved forward and backward. The amount of displacement of the liquid landing position can be reduced, and the image forming positions on both the front and back surfaces of the target can be reliably aligned.

  In order to achieve the above object, the transport method of the present invention includes a plurality of reference position marks provided at intervals in the transport direction along the length direction of the target with respect to the long target. Among these, the first detection step of detecting the position of the first reference position mark located downstream in the transport direction of the target, and the first detection step of the plurality of reference position marks detected in the first detection step A second detection step for detecting a position of a second reference position mark located upstream of the first reference position mark in the conveyance direction of the target; the first detection step; and the second detection step. The distance between the first reference position mark and the second reference position mark detected in the step in the transport direction of the target is set to a preset set distance. And a tensioning step of applying tension to the conveying direction with respect to the target.

  According to the said structure, the effect similar to invention of the said conveying apparatus is acquired.

1 is a side view schematically showing a printing system according to an embodiment of the present invention. FIG. 2 is a schematic plan view of a printer. 1 is a block diagram showing a control configuration of a printing system. The top view which shows the surface of the sheet | seat in which the image was formed. The top view which shows the back surface of the sheet conveyed to the printing position. The top view which shows the back surface of the sheet | seat extended | stretched from the state shown in FIG. The top view which shows the back surface of the sheet | seat in which the image was formed. The top view which shows the back surface of the sheet | seat extended | stretched from the state shown in FIG. (A) is a schematic diagram showing a state in which ink landing positions on the sheet from the recording head coincide with each other during forward movement and backward movement, and (b) shows a change in sheet thickness from the state shown in FIG. 9 (a). FIG. 9C is a schematic diagram showing the state, and in the state shown in FIG. 9B, the ink ejection timing is adjusted so that the landing positions of the ink on the sheet from the recording head in the forward movement and the backward movement coincide with each other. The schematic diagram which shows a state. The graph which shows the correlation of the magnitude | size of the tension | tensile_strength which acts on a sheet | seat, and the reduction | decrease amount of the thickness of a sheet | seat.

  As illustrated in FIG. 1, the printing system 100 includes an image generation device 110 that generates image data, a host device 120 that generates print data based on the image data received from the image generation device 110, and a reception from the host device 120. And a lateral scan ink jet printer (hereinafter simply referred to as “printer 11”) as an example of an image forming apparatus that prints an image based on the print data.

  The image generation device 110 includes, for example, a personal computer, and includes an image generation unit 112 that is constructed by a CPU in the main body 111 executing an image generation program. The user activates the image generation unit 112 and operates the input device 113 to create an image of a printed material that is a product on the monitor 114. For example, when the product is a label, a plurality of frame images are created by arranging a plurality of label images vertically and horizontally. When a predetermined operation is performed using the input device 113, image data relating to the image is transmitted to the host device 120 via the communication interface. Of course, it is also possible to read the image data from the image generation device 110 into the host device 120 by operating the host device 120.

  The host device 120 is configured by, for example, a personal computer, and includes a printer driver 122 that is constructed by a CPU in the main body 121 executing a printer driver program. The printer driver 122 generates print data based on the image data, and transmits the print data to the control device C provided in the printer 11. The control device C controls the printer 11 based on the print data received from the printer driver 122 and causes the printer 11 to print an image based on the print data. The monitor 123 displays a menu screen, an image to be printed, and the like. On the lower print setting screen displayed by the selection operation on the menu screen, it is possible to input and set management information relating to a product to be printed (for example, a label or the like) and various printing conditions.

  Here, the management information includes the product number and lot number of the product, and printing surface information for designating whether the printing is the front side or the back side in the case of duplex printing. The printing conditions include the type, size, print quality, and plate number of the print medium. There are two types of print media: paper and film. For example, the paper system includes high-quality paper, cast paper, art paper, and coated paper, and the film system includes synthetic paper, PET, PP, and the like. In addition, as the size of the print medium, a roll width or the like is set in the printer 11 on the premise that a roll around which a long print medium is wound is used. For the print quality, a plurality of types of recording modes that determine the printing resolution and recording method are prepared, and one of the recording modes is selected. Of course, the print resolution may be set instead of the recording mode. Also, the number of images (plates) to be overprinted in the case of performing overprinting for printing a plurality of times (multiple plates) in the same area of the print medium is set as the number of plates. When there are a plurality of versions, it is possible to display an image on the monitor 123 and designate an image for each version.

  Next, the configuration of the printer 11 shown in FIG. 1 will be described. In the following description, the terms “left-right direction” and “up-down direction” refer to the direction indicated by the arrow in FIG. In FIG. 1, the front side is the front side, and the back side is the rear side.

  As shown in FIG. 1, in a rectangular parallelepiped main body case 12 of a printer 11, a sheet 13 as an example of a long target is fed out from a roll R1 and printed on the sheet 13 by ink ejection. , A drying device (drying furnace) 16 as an example of a fixing unit that performs a drying process on the sheet 13 to which ink has adhered by printing, and the sheet 13 that has been subjected to the drying process is wound up as a roll R2. A winding unit 17 is provided.

  A region above the flat base 18 that vertically divides the inside of the main body case 12 is a printing chamber 15, and the printing region of the sheet 13 is supported at the center of the bottom of the printing chamber 15. The rectangular plate-shaped support base 19 is arranged in a state of being supported on the base 18. In the area below the base 18 in the main body case 12, the feeding unit 14 is disposed at a position on the left side that is upstream on the conveyance direction of the sheet 13, and at the right side that is on the downstream side. The winding part 17 is arrange | positioned in the position. A drying device 16 is disposed at a slightly upper position between the feeding unit 14 and the winding unit 17. The sheet 13 that has been subjected to the printing process on the support table 19 is dried in the drying device 16.

  As shown in FIG. 1, a winding shaft 20 extending in the front-rear direction is rotatably provided in the feeding portion 14, and a roll R <b> 1 on which the sheet 13 is previously wound in a roll shape can rotate integrally with the winding shaft 20. It is supported by. The sheet 13 is fed out from the roll R1 as the winding shaft 20 rotates. The sheet 13 fed out from the roll R1 is wound around the first roller 21 located on the right side of the winding shaft 20 and guided upward.

  As shown in FIGS. 1 and 2, the sheet 13 whose conveying direction is converted to the vertically upward direction by the first roller 21 is arranged at a position corresponding to the first roller 21 in the vertical direction on the left side of the support base 19. The conveying force is applied by being sandwiched between the paired first conveying rollers 22. The first conveying roller pair 22 includes a first driving roller 22a as an example of tension applying means connected to the conveying motor 61 (see FIG. 3) so as to be able to transmit power, and a sheet with respect to the first driving roller 22a. 13 and a first driven roller 22b disposed so as to face each other. The first driven rollers 22b are provided so as to be paired with an interval in the width direction of the sheet 13, and sandwich the edge in the width direction where the image is not printed on the sheet 13. . Then, the sheet 13 wound around the first driving roller 22a from the lower left side and converted in the conveyance direction to the horizontal right direction is brought into sliding contact with the upper surface of the support base 19 as the first driving roller 22a rotates. It has become.

  As shown in FIG. 1, a reference position mark or a two-dimensional code (identification information), which will be described later, is attached to the sheet 13 in the middle of the sheet path between the first roller 21 and the first transport roller pair 22. A hole forming mechanism 23 for penetrating and forming is provided. The hole forming mechanism 23 has a dot impact type print head (not shown), and a plurality of dot wires provided in the print head jump out toward the sheet 13, so that holes are formed in the sheet 13. Is formed to penetrate.

  As shown in FIGS. 1 and 2, a second transport roller pair 24 is provided on the right side of the support base 19 at a position facing the first transport roller pair 22 on the left side and the support base 19. . The second transport roller pair 24 is opposed to the second drive roller 24a connected to the transport motor 61 (see FIG. 3) so as to be able to transmit power, with the sheet 13 interposed therebetween. And the second driven roller 24b disposed in the. The second driven rollers 24b are provided so as to be paired with an interval in the width direction of the sheet 13, and sandwich the edge in the width direction where the image is not printed on the sheet 13. . The positions of the first driving roller 22 a and the second driving roller 24 a are adjusted so that the tops of the respective peripheral surfaces are at the same height as the upper surface of the support base 19.

  The sheet 13 conveyed from the upper surface of the support base 19 to the downstream side (right side) is wound around the second drive roller 24a from the upper right side, and the conveyance direction is converted to the vertically downward direction. As shown in FIG. 1, the sheet 13 is guided in a horizontal direction between the fourth roller 25 and the fifth roller 26 arranged on the lower side of the support base 19, and the conveyance path between the rollers 25 and 26 is It passes through the drying device 16 on the way. Further, the sheet 13 subjected to the drying process in the drying device 16 is guided to the fifth roller 26, the sixth roller 27, and the seventh roller 28 and is conveyed to the vicinity of the winding unit 17, and the conveyance motor 61 (FIG. The winding shaft 29 is rotated on the basis of the driving force (see 3) and is wound as the roll R2.

  For example, when double-sided printing is performed, surface printing is first performed on one surface which is the surface of the sheet 13. And when the sheet | seat 13 by which surface printing was given with respect to one side is wound up as the roll R2 while making the one side inside, the roll R2 of the winding part 17 will be removed, and the roll R2 will be It is set again in the feeding section 14 as a supply roll R1 at the time of printing on the back side. At this time, the sheet 13 from the roll R1 is applied to the first roller 21 in a feeding form shown by a two-dot chain line in FIG. 1 so that the other surface on the outside becomes the back surface and becomes a printing surface at the time of front surface printing. Wrapped. In the middle of the path of the sheet 13 between the drying device 16 and the winding unit 17, a die cutting processing machine 30 for die cutting a product portion (for example, a label) printed on the sheet 13 is provided. Thus, the product part die cutting process in the printer 11 is completed.

  As shown in FIGS. 1 and 2, a pair of guide rails 31 (indicated by a two-dot chain line in FIG. 1) extending in the left-right direction are provided on both sides in the front-rear direction of the support base 19 in the printing chamber 15. The pair of guide rails 31 guide the recording unit 32 so as to reciprocate in the main scanning direction X (left and right direction in FIG. 1). The recording unit 32 includes a rectangular carriage 33 and a plurality of recording heads 35 supported on the lower surface side of the carriage 33 via support plates 34. The carriage 33 is capable of reciprocating in the main scanning direction X along both guide rails 31 based on driving of a first carriage motor (hereinafter also referred to as “first CR motor 62” (see FIG. 3)). It is supported. The carriage 33 is also moved in the sub-scanning direction Y (the front-rear direction perpendicular to the paper surface in FIG. 1) based on the driving of a second carriage motor (hereinafter also referred to as “second CR motor 63” (see FIG. 3)). It is possible. As a result, the recording unit 32 can move in two directions, ie, the main scanning direction X and the sub-scanning direction Y.

  In the sheet 13, a certain range over almost the entire upper surface of the support 19 is a printing region R <b> 1, and the sheet 13 is intermittently conveyed by a conveyance amount unit corresponding to the printing region R <b> 1. A suction device 36 is provided below the support base 19. The suction device 36 is driven so as to exert a negative pressure on a number of suction holes (not shown) opened on the upper surface of the support table 19, and the sheet 13 is adsorbed on the upper surface of the support table 19 by the suction force due to the negative pressure. The Then, main scanning in which ink is ejected from the recording head 35 in the middle of the movement of the recording unit 32 in the main scanning direction X (main scanning) on the printing area of the sheet 13 positioned on the support base 19. Thus, a part of printing is performed, and after the main scanning, the sub scanning is performed in which the recording unit 32 is moved in the sub scanning direction Y to the next main scanning position. Then, printing is performed once (one frame) by repeating the main scanning M times. When the printing on the sheet 13 is finished once, the negative pressure of the suction device 36 is released, so that the suction of the sheet 13 onto the support base 19 is released, and the sheet 13 resumes intermittent conveyance after the release. It has come to be.

  In the middle of the path of the sheet 13 between the first transport roller pair 22 and the support base 19, a first position sensor as an example of a position sensor that optically reads a reference position mark or a two-dimensional code formed on the sheet 13. One reading sensor 37a is provided. Further, in the middle of the path of the sheet 13 between the support base 19 and the second transport roller pair 24, a first position sensor as an example of a position sensor that optically reads a reference position mark or a two-dimensional code formed on the sheet 13 is provided. A two reading sensor 37b is provided. Each reading sensor 37a, 37b emits light vertically downward toward the upper surface of the sheet 13, and a reference position mark on the sheet 13 out of the light output from the light emitting parts 38a, 38b. And light receiving portions 39a and 39b that receive light that passes through the two-dimensional code and is emitted vertically downward from the lower surface of the sheet 13, respectively. The light emitting portions 38a and 38b and the light receiving portions 39a and 39b are opposed to each other with the edge portion in the width direction (front-rear direction) of the sheet 13 on which the reference position mark and the two-dimensional code are formed on the sheet 13 being vertically sandwiched. It is arranged. The reading sensors 37a and 37b read the position of the reference position mark formed on the sheet 13 and the code arrangement of the two-dimensional code based on the light detection signals detected by the light receiving portions 39a and 39b. Yes.

  In addition, a maintenance device 40 for performing maintenance of the recording head 35 at the time of non-printing is provided in the non-printing area on the right end side in the printing chamber 15. The maintenance device 40 includes a cap 41 and a lifting device 42. The recording head 35 of the recording unit 32 that stands by at the home position during non-printing is capped by a cap 41 that is lifted by driving of the elevating device 42 so that thickening of ink in the nozzles is avoided. In addition, when a predetermined maintenance time comes, the suction pump (not shown) of the maintenance device 40 is driven under a capping state to forcibly discharge ink from the nozzles by making the inside of the cap 41 have a negative pressure, Cleaning is performed to remove thickened ink in the nozzle and bubbles in the ink.

  As shown in FIG. 1, a plurality (e.g., eight) of ink cartridges IC <b> 1 to IC <b> 8 respectively containing different color inks are detachably mounted in the main body case 12. The eight ink cartridges IC1 to IC8 are provided with inks such as black (K), cyan (C), magenta (M), yellow (Y), white (W), and clear (transparent color for overcoat), for example. Accommodate. Each of the ink cartridges IC1 to IC8 is connected to the recording head 35 through an ink supply path (not shown). Each recording head 35 ejects ink supplied from each ink cartridge IC <b> 1 to IC <b> 8 to print on the sheet 13.

  Next, the electrical configuration of the printing system 100 will be described with reference to FIG. The printer driver 122 in the host device 120 shown in FIG. 3 performs display control of various screens such as a menu screen and a print setting screen to be displayed on the monitor 123 as an example of notification means, and operates in the display state of each screen. A predetermined process corresponding to the operation signal input from the unit 124 is performed.

  The host device 120 includes a transfer control unit 129 that performs data transfer control. The transfer control unit 129 serially transfers the print data PD generated by the printer driver 122 to the printer 11 sequentially by a predetermined amount of packet data via the serial communication port U1. The printer driver 122 is capable of bidirectional communication with the control device C of the printer 11, transmits commands and control signals to the printer 11 via the transfer control unit 129, and receives responses from the printer 11. To do.

  The control device C on the printer 11 side shown in FIG. 3 is an example of an image formation control means for receiving print data PD from the host device 120 via the serial communication port U2 and performing various controls including print control. A controller 50 is provided. As shown in FIG. 3, the recording head 35 is connected to the controller 50 via a head control unit 51 (hereinafter simply referred to as “HCU 51”).

  As shown in FIG. 3, the controller 50 is connected to a linear encoder 52 provided along the movement path of the carriage 33 (that is, the recording unit 32). The controller 50 inputs a detection signal (encoder pulse signal) having a number of pulses proportional to the moving distance of the carriage 33 from the linear encoder 52. The controller 50 acquires the position (carriage position) of the carriage 33 in the main scanning direction X by counting the number of pulse edges of the encoder pulse signal, and based on the comparison result of the signal levels of the A-phase and B-phase encoder pulse signals. Get the carriage movement direction. Further, the controller 50 generates an ejection timing signal for determining the ejection timing of the recording head 35 based on the encoder pulse signal from the linear encoder 52. The controller 50 generates head control data that can be used by the recording head 35 from the image data in the print data PD, of which data for one main scanning (one pass) of the carriage 33 is recorded via the HCU 51 for each recording. Transmit to the head 35. The recording head 35 performs ejection control of the recording head 35 in main scanning in synchronization with the ejection timing signal from the nozzle to be ejected based on the head control data.

  As shown in FIG. 3, the controller 50 includes a CPU (Central Processing Unit) 53, an ASIC (Application Specific IC (Integrated Circuit for Specific Application)) 54, a ROM 55, a RAM 56, and a nonvolatile memory 57. The CPU 53 executes various tasks necessary for print control by executing a program stored in the ROM 55. Further, the ASIC 54 performs data processing of a recording system including image processing of the print data PD. Of course, the program including each task may be stored in the nonvolatile memory 57.

  As shown in FIG. 3, the control device C includes a mechanical controller 58 connected to the output side (control downstream side) of the controller 50 through the communication line SL1. The controller 50 instructs the mechanical controller 58 to drive the mechanical mechanism 59 by transmitting a print command included in the print data PD at a predetermined timing. The mechanical controller 58 drives and controls a mechanical mechanism 59 mainly including a transport system and a carriage drive system according to a predetermined sequence based on the print command received from the controller 50.

  When the controller 50 transmits a command to the mechanical controller 58 and receives a response from the mechanical controller 58 indicating that the sequence operation of the mechanical mechanism 59 according to the command has been completed, the procedure for transmitting the next command is taken. The drive timing of the mechanical mechanism 59 by the mechanical controller 58 is controlled.

  As shown in FIG. 3, the mechanical mechanism 59 includes a conveyance motor 61 that constitutes a conveyance system, and a first CR motor 62 and a second CR motor 63 that constitute a carriage drive system. A transport motor 61, a first CR motor 62, and a second CR motor 63 are connected to the mechanical controller 58 via a motor drive circuit 60, respectively. The transport motor 61 is for driving a transport mechanism constituted by the rollers 21, 22a, 22b, 24a, 24b, 25-28 and the shafts 20, 29 and the like.

  The first CR motor 62 is a power source for driving the carriage 33 in the main scanning direction X, and the second CR motor 63 is a power source for driving the carriage 33 in the sub-scanning direction Y. In the lateral scan method, the carriage 33 is driven in the main scanning direction X and ink is ejected from the recording head 35 in the middle of the driving to perform printing for one pass, and the carriage 33 is predetermined in the sub-scanning direction Y. The sub-scanning in which the recording head 35 is shifted to the printing position of the next pass by driving only the pitch is repeated. Then, a printing process is performed by performing a plurality of passes by performing a predetermined number of main scans (passes).

  Furthermore, as shown in FIG. 3, the mechanical mechanism 59 includes a drying device 16, a suction device 36, and a maintenance device 40, which are electrically connected to a mechanical controller 58. The mechanical controller 58 is connected with a first reading sensor 37a, a second reading sensor 37b, a power switch 65, and an encoder 66 as an input system. An on signal when the power switch 65 is turned on and an off signal when the power switch 65 is turned off are transmitted to the controller 50 via the mechanical controller 58.

  In addition, the mechanical controller 58 drives and controls the motors 61 to 63, the suction device 36, and the maintenance device 40 in accordance with various commands received from the controller 50 through the communication line SL1. The encoder 66 detects the rotation of the rotation shaft of the conveyance drive system using the conveyance motor 61 as a power source, and the mechanical controller 58 uses the detection signal (encoder pulse signal) of the encoder 66 to convey the sheet 13. And the transport position is detected.

  At the time of printing, the control device C drives the conveyance motor 61 to convey the sheet 13 so as to place the next printing area (frame) of the sheet 13 on the support base 19, and after the conveyance of the sheet, An adsorption operation for adsorbing the print area to the support 19, a printing operation on the sheet 13 by the recording head 35, and an adsorption release operation for releasing the adsorption of the sheet 13 after completion of printing for one time (one frame) are performed. At this time, the printing operation is performed by ejecting ink droplets from the recording head 35 during the movement of the recording unit 32 in the main scanning direction X. In this printing operation, the carriage 33 is moved in the main scanning direction X by driving the first CR motor 62 (one-pass operation) and the carriage 33 is moved in the sub-scanning direction Y every time one pass is completed. This is performed by repeating the path (for 4 or 8 paths).

Next, the operation of the printer 11 configured as described above will be described below, particularly focusing on the operation when image printing processing is sequentially performed on the front and back surfaces of the sheet 13.
When the image printing process is performed on the surface of the sheet 13, first, the controller 50 drives the transport motor 61 so that the surface of the sheet 13 faces upward on the support base 19. Transport. Here, as shown in FIG. 4, hole forming regions S <b> 1 are provided at intervals in the conveyance direction of the sheet 13 at positions that become one edge in the width direction of the sheet 13. And in these hole formation area S1, the several through-hole 67 is formed so that the sheet | seat 13 may be penetrated in the thickness direction.

  Then, when the sheet 13 is conveyed toward the downstream side in the conveying direction, the through holes 67 cause the light emitting units 38a and 38b and the light receiving units 39a and 39b to move up and down in the first reading sensor 37a and the second reading sensor 37b. Is crossed in the conveyance direction of the sheet 13. Therefore, each of the reading sensors 37a and 37b is based on a detection signal of light detected from the light receiving portions 39a and 39b through the through holes 67 among the light emitted from the light emitting portions 38a and 38b. The transport positions of these through holes 67 on 13 are read. The detection area of the through hole 67 by each of the reading sensors 37a and 37b has a rectangular shape extending in the conveyance direction of the sheet 13, and the size of the detection area in the conveyance direction of the sheet 13 is the hole formation area in the same direction. It is set larger than the dimension of S1.

  The hole forming area S1 provided in the sheet 13 is arranged with respect to the detection area of the through hole 67 in both the reading sensors 37a and 37b provided on both sides in the conveying direction of the sheet 13 with the support 19 interposed therebetween. Then, both the reading sensors 37a and 37b measure the distance L1 at which these hole forming areas S1 are separated in the conveyance direction of the sheet 13 based on the light detection signals in the light receiving portions 39a and 39b.

  Specifically, as the first detection step and the second detection step, the controller 50 detects the upper left corner (sheet) shown in FIG. 4 in the hole formation region S1 arranged in the detection region of each of the reading sensors 37a and 37b. 13 is an output signal from the reading sensors 37a and 37b that read the conveying position of the through hole 67a formed in the partition area S1a at the upstream side in the conveying direction 13 and at the corner located on the edge side in the width direction of the sheet 13. Based on this, the distance L1 at which these through holes 67a are separated in the conveyance direction of the sheet 13 is measured.

  And the controller 50 stops conveyance of the sheet | seat 13, when the measurement of the separation distance of said through-hole 67a is complete | finished. Then, the controller 50 determines the two-dimensional code that has already been read by the first reading sensor 37a during the conveyance process of the sheet 13, that is, the hole forming area S1 on the support base 19 other than the partition area S1a. Based on the detection signal read by the first reading sensor 37a using the code array of the through holes 67b formed in the partition region S1b as a two-dimensional code, the related information of the image formed on the sheet 13 is read. In this related information, the print job ID information of the image formed on the sheet 13 and the print position are aligned by a specific reference position mark among all the frame images to be printed included in the print job ID information. The number of print pages of the frame image to be printed, the number of frame images whose print positions are aligned by a specific reference position mark, and the like are included.

  In the present embodiment, the two-dimensional code formed in the three hole forming areas S1 located on the support base 19 in FIG. 4 includes the same print job ID information as image related information. In addition, in the related information of the images included in these two-dimensional codes, the number of images in the frame image group in which the print positions are aligned by the reference position marks provided adjacent to each two-dimensional code is 10 respectively. It has become. The frame images 69 arranged in a 2 × 5 grid pattern are printed in the frame image forming regions 68 individually corresponding to the respective reference position marks in the print region R1 of the sheet 13. The In the present embodiment, three frame image forming areas 68 are included for the print area R1 of the sheet 13.

  Further, the controller 50 forms a frame image according to the number of frame images whose print positions are aligned with reference to the position of the through hole 67a serving as a reference position mark among the related information of the image included in the two-dimensional code. The print position of each frame image 69 in the area 68 is calculated. The controller 50 generates a timing signal of the ejection timing of ink to be ejected from the nozzles based on the calculated printing position of each frame image 69, and the recording head 35 in main scanning in synchronization with the generated timing signal. By performing this ejection control, each frame image 69 is accurately printed at a desired position in the frame image forming region 68 of the sheet 13.

  In this embodiment, when the controller 50 prints the frame image 69 on the frame image forming area 68 of the sheet 13, the controller 50 stores the image data in the print data input as a print job to the host device 120. Among them, the number of printed pages of the image data printed on the sheet 13 and the number of pages of the frame image forming area 68 read through the two-dimensional code formed on the sheet 13 are collated, and an appropriate image for the sheet 13 is checked. Is printed at the correct position.

  Specifically, two of the three hole forming areas S1 located on the support base 19 in FIG. 4 are formed in the hole forming area S1 located on the upstream side (left side in FIG. 4) in the conveyance direction of the sheet 13. In the dimension code, the image content of “building” is set as the image content of the frame image group in the frame image forming area 68 on the third page with respect to the surface of the sheet 13 corresponding to the two-dimensional code. Also, the two-dimensional code formed in the hole forming region S1 located on the downstream side (right side in FIG. 4) in the conveyance direction of the sheet 13 among the three hole forming regions S1 located on the support base 19 in FIG. The image content of “apple” is set as the image content of the frame image group in the frame image forming area 68 of the first page with respect to the surface of the sheet 13 corresponding to the two-dimensional code. Further, among the three hole forming areas S1 located on the support base 19 in FIG. 4, the hole forming area S1 is located in the center in the transport direction of the sheet 13 sandwiched between the two hole forming areas S1. In the two-dimensional code, the image content of “star” is set as the image content of the frame image group in the frame image forming area 68 of the second page with respect to the surface of the sheet 13 corresponding to the two-dimensional code.

  When the image printing process for the front surface of the sheet 13 is completed, the image printing process for the back surface of the sheet 13 is started. Here, as shown in FIG. 5, the position of the through-hole 67 in the conveyance direction of the sheet 13 when the image is printed on the front surface of the sheet 13 and when the image is printed on the back surface of the sheet 13. Invert so that the relationship is a mirror image relationship. For this reason, as the first detection step and the second detection step, the controller 50 detects the upper right corner shown in FIG. 5 in the hole formation region S1 of the sheet 13 (the downstream side in the conveyance direction of the sheet 13 and the width of the sheet 13). Based on the output signals from the first reading sensor 37a and the second reading sensor 37b that read the conveying position of the through hole 67a formed in the partition area S1a (the corner located on the edge side in the direction), these through holes 67a , The distance L2 separated in the conveyance direction of the sheet 13 is measured.

  Here, in the printer 11 of the present embodiment, since the heat is applied to the sheet 13 when the drying device 16 fixes the image printed on the surface of the sheet 13 to the sheet 13, the sheet 13 is thermally contracted. Resulting in. Therefore, when the image is printed on the back surface of the sheet 13 that has been subjected to the heat fixing process, the through hole 67a is formed in the sheet 13 as compared with the case where the image is printed on the surface of the sheet 13. The separation distance in the transport direction decreases.

  Therefore, in the printer 11 according to the present embodiment, when the image printing process is performed on the back surface of the sheet 13, the controller 50 controls the sheet 13 more than the support base 19 through the drive control of the transport motor 61 as a tension applying step. The rotation driving of the driving roller 24a located on the downstream side in the conveying direction is stopped, and the first driving roller 22a located on the upstream side in the conveying direction of the sheet 13 with respect to the support base 19 is reversely driven. Then, the conveyance force which goes to the upstream of the conveyance direction of the sheet | seat 13 from the 1st drive roller 22a is provided to the part located on the support stand 19 in the sheet | seat 13, and the sheet | seat 13 is directed toward the upstream of the conveyance direction. Tension acts to stretch. And the said through-hole 67a increases the separation distance in the conveyance direction of the sheet | seat 13 gradually.

  Then, the controller 50 monitors the movement amount of the through hole 67 detected by the reading sensors 37a and 37b based on the detection signals of the through holes 67 output from the first reading sensor 37a and the second reading sensor 37b. While controlling the driving amount of the transport motor 61. In this embodiment, as shown in FIG. 6, the controller 50 is configured such that the distance between the through holes 67 a provided on both sides in the conveyance direction of the sheet 13 with the support base 19 interposed therebetween is the distance L1 (= L2 + d1). When it is determined that the sheet 13 has been reached, the driving of the transport motor 61 is stopped, whereby the stretching of the sheet 13 by the first driving roller 22a is stopped. That is, the controller 50 applies tension to the sheet 13 within a range in which the amount of stretching in the conveyance direction based on the application of tension in the sheet 13 does not exceed a preset threshold value. At this time, the size in the conveyance direction of the sheet 13 is substantially the same between when the image is printed on the front surface of the sheet 13 and when the image is printed on the back surface of the sheet 13. That is, the sheet 13 is stretched in the transport direction by the first drive roller 22a so that the thermal shrinkage caused by the thermal fixing of the image printed on the surface is offset.

  The controller 50 continuously monitors the driving load of the transport motor 61 while the first driving roller 22a extends the sheet 13. The controller 50 determines that the first drive roller 22a, which is the drive target of the transport motor 61, is idle when the drive load of the transport motor 61 is drastically reduced, and the first drive roller 22a It is detected that the sheet 13 to be conveyed is broken. In this respect, in the present embodiment, the controller 50 constitutes an example of a detection unit that detects whether or not the sheet 13 is broken. At the same time, the controller 50 transmits a command and a control signal to the host device 120 via the transfer control unit 129 and causes the monitor 123 to display an error notification.

  Then, the controller 50 determines the two-dimensional code that the first reading sensor 37a has already completed reading in the process of transporting the sheet 13, that is, the hole forming area S1 on the support base 19 in FIG. Based on the detection signal read by the first reading sensor 37a using the code array of the through holes 67b formed in the other partition region S1b as a two-dimensional code, the related information of the image formed on the sheet 13 is read.

  Here, as described above, the code arrangement of the through holes 67 is inverted so that the positional relationship in the conveyance direction of the sheet 13 is a mirror image relationship. Therefore, the controller 50 performs image processing for inverting the code arrangement of the through holes 67 detected by the first reading sensor 37a to the left and right. Then, the same code arrangement is read as a two-dimensional code from both the front and back sides of the sheet 13 through the through hole 67, and related information of an image formed on the sheet 13 is read.

  In the present embodiment, the two-dimensional code formed in the three hole forming areas S1 located on the support base 19 in FIG. 6 includes the same print job ID information as image related information. In addition, in the related information of the images included in these two-dimensional codes, the number of images in the frame image group in which the print positions are aligned by the reference position marks provided adjacent to each two-dimensional code is 10 respectively. It has become.

  Then, as shown in FIG. 7, the frame image forming areas 70 individually corresponding to the respective reference position marks in the print area R1 of the sheet 13 are arranged so as to form a 2 × 5 grid pattern. Each frame image 71 is printed. In the present embodiment, three frame image forming regions 70 are included for the print region R1 of the sheet 13.

  Further, the controller 50 forms a frame image according to the number of frame images whose print positions are aligned with reference to the position of the through hole 67a serving as a reference position mark among the related information of the image included in the two-dimensional code. The print position of each frame image in the area 70 is calculated. The controller 50 generates a timing signal of the ejection timing of the ink to be ejected from the nozzles based on the calculated printing position of each frame image 71, and the recording head 35 in the main scanning in synchronization with the generated timing signal. By performing this ejection control, each frame image 71 is accurately printed at a desired position in the frame image forming area 70 of the sheet 13.

  The sheet 13 is formed with a through-hole 67 that functions as a reference position mark in the thickness direction of the sheet 13, and the first reading sensor 37 a and the second reading sensor 37 b are penetrated from both the front and back sides of the sheet 13. The position of the hole 67 is detected. For this reason, images are printed on both the front and back surfaces of the sheet 13 using a common reference position mark or two-dimensional code, so that images that are accurately aligned are printed on both the front and back surfaces of the sheet 13. It has become so.

  Further, as described above, when an image is printed on the back surface of the sheet 13, the sheet 13 has a first shrinkage so as to cancel out the thermal shrinkage caused by the heat fixing of the image printed on the front surface. The film is stretched in the transport direction by the drive roller 22a. Specifically, the interval between the hole forming regions S1 in the conveyance direction of the sheet 13 is substantially equal between when the image is printed on the front surface of the sheet 13 and when the image is printed on the back surface of the sheet 13. Thus, the sheet 13 is stretched.

  Therefore, the case where an image is printed on the front surface of the sheet 13 and the case where an image is printed on the back surface of the sheet 13 without depending on the magnitude of the thermal contraction amount of the sheet 13 when the image is thermally fixed. The distance between the through holes 67a arranged with the support base 19 in between is always substantially equal. Therefore, each frame image 71 is reliably printed at a desired position with respect to the back surface of the sheet 13.

  In the present embodiment, when the controller 50 prints the frame image 71 on the back surface of the sheet 13, the controller 50 applies to the sheet 13 among the image data in the print data input as a print job from the host device 120. The number of printed pages of the image data to be printed is compared with the number of pages of the frame image forming area 70 read through the two-dimensional code formed on the sheet 13, so that an appropriate image is accurately positioned on the sheet 13. It is supposed to be printed on.

  Specifically, two of the three hole formation areas S1 located on the support base 19 in FIG. 7 are formed in the hole formation area S1 located on the upstream side (left side in FIG. 7) in the sheet 13 conveyance direction. In the dimension code (that is, the two-dimensional code formed in the hole forming region S1 located on the upstream side in the conveyance direction of the sheet 13 shown in FIG. 4), the first page with respect to the back surface of the sheet 13 corresponding to the two-dimensional code. As the image content of the frame image group in the frame image forming area 70, the vertical and horizontal arrangement positions of the frame images 71 with the character string “building” and the character string together with the reference position mark in the frame image group are used. A character string “MN” (M: vertical column number, N: horizontal column number) is set.

  In addition, among the three hole forming areas S1 located on the support base 19 in FIG. 7, the two-dimensional code (in the hole forming area S1 located on the downstream side (right side in FIG. 7) in the conveyance direction of the sheet 13 ( That is, in the two-dimensional code formed in the hole forming region S1 located on the upstream side in the conveyance direction of the sheet 13 shown in FIG. 4, the frame image of the third page with respect to the surface of the sheet 13 corresponding to the two-dimensional code. As the image content of the frame image group in the formation area 70, “M” indicating the vertical and horizontal arrangement positions of each frame image 71 with the above-mentioned reference position mark as a reference in this frame image group together with the character string “Apple”. The character string “-N” (M: vertical column number, N: horizontal column number) is set.

  Further, in the three hole forming areas S1 located on the support base 19 in FIG. 7, the hole forming area S1 is located in the center in the transport direction of the sheet 13 sandwiched between the two hole forming areas S1. In the two-dimensional code, as the image content of the frame image group in the frame image forming area 70 on the second page with respect to the surface of the sheet 13 corresponding to the two-dimensional code, the frame image together with the character string “star” and the frame image In the group, a character string “MN” (M: vertical column number, N: horizontal column number) indicating the vertical and horizontal arrangement positions of each frame image 71 with reference to the reference position mark is set. ing.

  Further, when an image printing process is performed on the printing area R1 including the frame image forming area 70 from the first page to the third page on the back surface of the sheet 13, the controller 50 performs driving control of the conveyance motor 61. Then, the first drive roller 22a located upstream of the support base 19 in the conveyance direction of the sheet 13 is driven in reverse. Then, the conveyance force which goes to the upstream of the conveyance direction of the sheet | seat 13 from the 1st drive roller 22a is provided to the part located on the support stand 19 in the sheet | seat 13, and the sheet | seat 13 is directed toward the upstream of the conveyance direction. Tension acts to stretch. And the said through-hole 67a increases the separation distance in the conveyance direction of the sheet | seat 13 gradually.

  Then, the controller 50 monitors the movement amount of the through hole 67 detected by the reading sensors 37a and 37b based on the detection signals of the through holes 67 output from the first reading sensor 37a and the second reading sensor 37b. While controlling the driving amount of the transport motor 61. As shown in FIG. 8, the controller 50 determines that the stretch amount of the sheet 13 is a predetermined length based on the detection results of the reading sensors 37 a and 37 b provided on both sides in the conveyance direction of the sheet 13 with the support base 19 interposed therebetween. When it is determined that the distance d2 has been reached, the driving of the transport motor 61 is stopped, whereby the stretching of the sheet 13 by the first driving roller 22a is stopped.

  Note that the predetermined length d2 is set to be approximately the same as the size at which the sheet 13 is expected to be thermally contracted in the conveyance direction when the image printed on the back surface of the sheet 13 is thermally fixed. That is, even when the image printed on the back surface of the sheet 13 is heat-fixed, the sheet 13 is preliminarily transported by the first drive roller 22a so that the thermal shrinkage caused by the heat-fixing of the image is offset. Stretched. Therefore, between the state after the image is printed on the back surface of the sheet 13 and the state after the image printed on the back surface of the sheet 13 is thermally fixed, the stretch amount of the sheet 13 in the transport direction is almost equal. The distances between the hole forming areas S1 in the conveyance direction of the sheet 13 are also substantially equal. Therefore, according to the printer 11 of this embodiment, the processing machine 30 provided at the most downstream position in the conveyance direction of the sheet 13 is used, and the interval between the hole forming areas S1 (that is, printing on the back surface of the sheet 13 is performed as described above. The image is accurately die-cut from the sheet 13 on which the interval between the images is set.

  By the way, in the printer 11 of the present embodiment, the recording head 35 is scanned in the main scanning direction, and ink is ejected from the nozzles of the recording head 35 toward the sheet 13 at a predetermined ejection timing. An image is printed.

  Here, as shown in FIG. 9A, the landing position of the ink ejected from the recording head 35 moving to one side in the main scanning direction X (right side in FIG. 9A) and the other in the main scanning direction. Assume that the ejection timing of the ink from the recording head 35 is set so that the landing position of the ink ejected from the recording head 35 that moves to the side (the left side in FIG. 9A) coincides.

  In this case, as shown in FIG. 9B, if the sheet 13 is stretched in the conveyance direction in accordance with the thermal contraction of the sheet 13, one side in the main scanning direction is accompanied by a decrease in the thickness of the sheet 13. The landing position of the ink ejected from the recording head 35 that moves to the other side does not coincide with the landing position of the ink ejected from the recording head 35 that moves to the other side in the main scanning direction.

  However, in this case, in the printer 11 of the present embodiment, the ejection timing of the ink from the recording head 35 that moves to one side in the main scanning direction is delayed according to the decrease in the thickness of the sheet 13. As a result, the landing position of the ink ejected from the recording head 35 moving to one side in the main scanning direction matches the landing position of the ink ejected from the recording head 35 moving to the other side in the main scanning direction. Thus, a high-quality image can be printed on the sheet 13.

Specifically, as shown in FIG. 10, the operator shows a correlation between the magnitude T of the tension applied to the sheet 13 and the amount of decrease Δx in the thickness of the sheet 13 accompanying the tension. The graph is determined in advance by experiments or the like, and the determined graph data is stored in the ROM 55. Then, the controller 50, by measuring the magnitude of the driving load of the transport motor 61 to estimate the magnitude T ₁ of the tension acting from the first drive roller 22a through driven to rotate in the seat 13 of the conveying motor 61 .

And then, the controller 50 reads out the graph above the ROM 55, the read graph, by inclusion of estimated value T ₁ of the amount of tension acting on the seat 13, the seat with the tensioning A thickness reduction amount Δx ₁ of 13 is estimated. Then, as shown in FIG. 9C, the controller 50 delays the ejection timing of the ink from the recording head 35 that moves to one side in the main scanning direction based on the estimated thickness reduction amount of the sheet 13. Adjust. As a result, even if the thickness of the sheet 13 is changed with the application of tension, the controller 50 has a landing position of ink from the recording head 35 that moves to one side in the main scanning direction and the other in the main scanning direction. Accordingly, the landing position of the ink from the recording head 35 that moves to the side coincides, and a high-quality image can be printed on the sheet 13.

According to the above embodiment, the following effects can be obtained.
(1) Even when the sheet 13 is contracted in the transport direction by performing a predetermined process on the sheet 13 at a position corresponding to each reference position mark, the first driving roller 22a is read by the reading sensor 37a. , 37b, tension is applied to the sheet 13 so that the distance between the reference position marks becomes a preset distance. Therefore, a predetermined process can be performed at an accurate position on both the front and back surfaces of the sheet 13.

  (2) The first drive roller 22a applies tension to the sheet 13 within a range in which the amount of extension in the conveyance direction based on the application of tension in the sheet 13 does not exceed a preset threshold value. For this reason, the extension amount of the sheet 13 in the conveyance direction is limited, and an excessive tension is avoided from acting on the sheet 13, so that the sheet 13 can be prevented from breaking.

  (3) The controller 50 detects whether or not the sheet 13 is broken, and performs error notification when the break of the sheet 13 is detected. Therefore, the operator can quickly and reliably grasp that the sheet 13 is broken.

  (4) Since the tension is applied to the sheet 13 so as to cancel out the thermal shrinkage of the sheet 13 when the image is thermally fixed to the sheet 13, the image from the sheet 13 subjected to the heat fixing process The die cutting process can be performed more accurately.

  (5) Even if the sheet 13 is thermally contracted when the image formed on the surface of the sheet 13 is thermally fixed, the sheet 13 is stretched by applying tension to the back surface of the thermally contracted sheet 13. In this state, an image forming process is performed. Therefore, even when the image is heat-fixed on the heat-shrinkable sheet 13, the image forming process can be accurately performed on both the front and back surfaces of the sheet 13.

  (6) Generally, when an image is thermally fixed to the sheet 13, the thickness of the sheet 13 changes due to the application of tension. Then, the amount of deviation of the ink landing position when the recording head 35 moves forward and backward changes. In this regard, according to the above-described embodiment, the adjustment amount of the ejection timing of the ink from the recording head 35 is changed according to the extension amount of the sheet 13 by applying the tension, so that the recording head 35 is moved forward and backward. The amount of displacement of the ink landing position at the time can be reduced, and the image forming positions on the front and back surfaces of the sheet 13 can be reliably aligned.

The above embodiment may be changed to another embodiment as described below.
In the above embodiment, the ejection timing of the ink from the recording head 35 that moves to the other side in the main scanning direction may be advanced according to the amount of decrease in the thickness of the sheet 13.

  In the above embodiment, the sheet 13 may not be stretched in advance before the image printed on the back surface of the sheet 13 is thermally fixed to the sheet 13. Even in such a configuration, the position where the image is removed from the sheet 13 by the processing machine 30 after considering the amount of thermal contraction of the sheet 13 in the stage where the image printed on the back surface of the sheet 13 is thermally fixed to the sheet 13. Is set, the image can be accurately punched from the sheet 13.

  In the above embodiment, the sheet 13 may be stretched in advance before the image printed on the surface of the sheet 13 is thermally fixed to the sheet 13. In such a configuration, by setting a dimension corresponding to the amount of thermal shrinkage of the sheet 13 at the stage of thermally fixing the image printed on the surface of the sheet 13 to the sheet 13, the stretching amount of the sheet 13 is set. It is also possible to employ a configuration in which the sheet 13 is not stretched in advance before printing an image on the back surface.

  In the above embodiment, when the controller 50 detects that the sheet 13 is broken based on the driving load of the transport motor 61, the controller 50 notifies the monitor 123 of the host device 120 of an error. Alternatively, the rotational drive of the transport motor 61 may be forcibly stopped.

  In the above embodiment, when the image is printed on the back surface of the sheet 13, the separation distance between the through holes 67 a provided on both sides in the conveyance direction of the sheet 13 with the support 19 interposed therebetween is You may set so that it may become smaller than the separation distance of said through-hole 67a at the time of performing the printing process of an image with respect to the surface. That is, when the image printed on the back surface is heat-fixed, the sheet 13 does not necessarily have to be stretched to such an extent that the thermal shrinkage caused by the heat fixing of the image is offset.

  In the above embodiment, the controller 50 constantly monitors the driving load of the conveyance motor 61, and within a range where the magnitude of the tension acting on the sheet 13 from the first driving roller 22a does not exceed a predetermined threshold. Tension may be applied to 13. Even in such a configuration, it is possible to prevent the amount of stretching of the sheet 13 from being excessive, and thus it is possible to avoid the sheet 13 from being broken in the transport direction.

  In the above embodiment, the sheet 13 on which the reference position mark and the two-dimensional code are printed on both the front and back surfaces may be the target of the printing process. Further, a mechanism for printing the reference position mark and the two-dimensional code on both the front and back surfaces of the sheet 13 may be provided on the conveyance path of the sheet 13.

  In the above embodiment, as a reading means for reading the reference position mark and the two-dimensional code, the code arrangement of the through holes 67 indicating the reference position mark and the two-dimensional code is arranged one by one for each code row arranged in the width direction of the sheet 13. You may make it read. In this case, at least one through-hole 67 is formed in all the code strings if the reading end timing of the reference position mark and the two-dimensional code is determined by counting the number of code strings that have been read. It is desirable. Further, the reading means for reading the reference position mark and the two-dimensional code is not limited to the optical sensor, and a sensor of another detection method such as a contact sensor may be adopted.

  In the above embodiment, the image forming apparatus is not limited to the lateral scan type printer 11 and may be a serial printer, a line printer, or a page printer. Furthermore, the present invention is not limited to the ink jet type, and can be applied to a dot impact type printing apparatus.

  In the embodiment, the ink jet printer 11 is employed as the image forming apparatus, but a fluid ejecting apparatus that ejects or ejects fluid other than ink may be employed. Further, the present invention can be used for various liquid ejecting apparatuses including a liquid ejecting head that ejects a minute amount of liquid droplets. In this case, the droplet refers to the state of the liquid ejected from the liquid ejecting apparatus, and includes liquid droplets having a granular shape, a tear shape, and a thread shape. The liquid here may be any material that can be ejected by the liquid ejecting apparatus. For example, it may be in a state in which the substance is in a liquid phase, such as a liquid with high or low viscosity, sol, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, liquid metals (metal melts ) And liquids as one state of the substance, as well as those obtained by dissolving, dispersing or mixing particles of a functional material made of solid materials such as pigments and metal particles in a solvent. Further, representative examples of the liquid include ink and liquid crystal as described in the above embodiment. Here, the ink includes general water-based inks and oil-based inks, and various liquid compositions such as gel inks and hot-melt inks. As a specific example of the liquid ejecting apparatus, for example, a liquid containing a material such as an electrode material or a coloring material used for manufacturing a liquid crystal display, an EL (electroluminescence) display, a surface emitting display, a color filter, or the like in a dispersed or dissolved state. A liquid ejecting apparatus for ejecting may be used. Further, it may be a liquid ejecting apparatus that ejects a bio-organic matter used for biochip production, a liquid ejecting apparatus that ejects a liquid that is used as a precision pipette and serves as a sample, a printing apparatus, a microdispenser, or the like. In addition, transparent resin liquids such as UV curable resin to form liquid injection devices that pinpoint lubricant oil onto precision machines such as watches and cameras, and micro hemispherical lenses (optical lenses) used in optical communication elements. A liquid ejecting apparatus that ejects a liquid onto the substrate or a liquid ejecting apparatus that ejects an etching solution such as an acid or an alkali to etch the substrate may be employed. The present invention can be applied to any one of these liquid ejecting apparatuses. Further, the fluid may be a granular material such as toner. In addition, the fluid referred to in this specification does not include a fluid consisting only of a gas.

  DESCRIPTION OF SYMBOLS 11 ... Printer as an example of a conveying apparatus, 13 ... Sheet as an example of a target, 16 ... Drying apparatus as an example of fixing means, 22a ... The 1st drive roller as an example of tension | tensile_strength provision means, 37a ... Example of a position sensor First reading sensor as 37b ... Second reading sensor as an example of position sensor, 50 ... Controller as an example of image formation control means and detection means, 67a ... Example of first reference position mark and second reference position mark As a through hole, 123... A monitor as an example of a notification means.

Claims (8)

A position sensor for detecting the positions of the first reference position mark and the second reference position mark provided at an interval in the transport direction along the length direction of the target with respect to the long target;
Based on the detection result of the position sensor, the separation distance between the first reference position mark and the second reference position mark in the transport direction of the target is set to a predetermined set distance with respect to the target. And a tension applying means for applying tension in the transport direction. In the conveyance apparatus of Claim 1,
The said tension | tensile_strength provision apparatus provides the tension | tensile_strength with respect to the said target within the range in which the amount of expansion | extension of the conveyance direction based on the said tension | tensile_strength provision in the said target does not exceed the preset threshold value. In the conveyance apparatus of Claim 1 or Claim 2,
Detecting means for detecting whether or not the target is broken;
An informing means for informing an error when the detecting means detects a breakage of the target. The conveying apparatus as described in any one of Claims 1-3,
Image forming control means for performing image forming processing on a target conveyed by the conveying device;
An image forming apparatus comprising: a fixing unit configured to thermally fix an image formed on the target by the image forming control unit. The image forming apparatus according to claim 4.
The tension applying unit is configured to apply the heat generated by the fixing unit to the target on which the image forming process has been performed by the image forming control unit before the image is thermally fixed on the target by the fixing unit. An image forming apparatus, wherein tension is further applied in the transport direction of the target by a distance corresponding to an estimated value of the amount of thermal shrinkage of the target accompanying fixing processing. The image forming apparatus according to claim 4 or 5, wherein:
The image formation control unit is configured to sequentially execute image formation processing on the front surface and the back surface of the target,
The image forming apparatus according to claim 1, wherein the tension applying unit further applies tension to the target before image forming processing is performed on at least the back surface of the image forming processing on the front surface and the back surface of the target. The image forming apparatus according to any one of claims 4 to 6,
The image formation control means is configured to reciprocate in a direction crossing the target transport direction and eject liquid to the target to form an image, and an image forming position during forward movement and a backward movement The liquid ejection timing can be adjusted in accordance with the amount of deviation from the image forming position, and the adjustment amount of the liquid ejection timing is changed based on the amount of extension of the target by applying tension. An image forming apparatus. Of the plurality of reference position marks provided at intervals in the transport direction along the length direction of the target with respect to the long target, the first reference is located downstream in the transport direction of the target. A first detection step for detecting the position of the position mark;
Among the plurality of reference position marks, a position of a second reference position mark located upstream in the transport direction of the target from the first reference position mark detected in the first detection step is detected. A second detection step;
The separation distance between the first reference position mark and the second reference position mark in the target transport direction detected in the first detection step and the second detection step is a preset set distance. Thus, a tension applying step for applying tension to the target in the transport direction is provided.

Images